:root {
      --primary: #4f46e5;
      --primary-dark: #3730a3;
      --secondary: #ff5722;
      --accent-cyan: #06b6d4;
      --accent-yellow: #f59e0b;
      --accent-green: #10b981;
      --dark-text: #0f172a;
      --muted-text: #475569;
      --light-text: #64748b;
      --bg-light: #f8fafc;
      --bg-white: #ffffff;
      --card-border: #e2e8f0;
      --container-max: 1240px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
      background-color: var(--bg-light);
      color: var(--dark-text);
      line-height: 1.6;
    }

    body {
      background: radial-gradient(circle at 10% 20%, rgba(79, 70, 229, 0.04) 0%, transparent 40%),
                  radial-gradient(circle at 90% 80%, rgba(255, 87, 34, 0.04) 0%, transparent 40%),
                  var(--bg-light);
      min-height: 100vh;
      overflow-x: hidden;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    .container {
      width: 100%;
      max-width: var(--container-max);
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }

    /* 顶部导航 */
    header.site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 2px solid var(--card-border);
    }

    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .brand-box {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .ai-page-logo {
      height: 40px;
      width: auto;
      display: block;
    }

    .brand-tagline {
      font-weight: 800;
      font-size: 1.15rem;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
      list-style: none;
    }

    .nav-links li a {
      display: inline-block;
      padding: 8px 14px;
      font-weight: 600;
      font-size: 0.92rem;
      color: var(--dark-text);
      border-radius: 6px;
      transition: all 0.2s ease;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      color: var(--primary);
      background: rgba(79, 70, 229, 0.08);
    }

    .nav-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .btn-nav-primary {
      background: var(--primary);
      color: #ffffff !important;
      padding: 9px 18px;
      border-radius: 8px;
      font-weight: 700;
      font-size: 0.9rem;
      box-shadow: 0 4px 12px rgba(79, 70, 229, 0.25);
      transition: transform 0.2s, background 0.2s;
    }

    .btn-nav-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
    }

    .mobile-menu-toggle {
      display: none;
      background: transparent;
      border: none;
      font-size: 1.6rem;
      color: var(--dark-text);
      cursor: pointer;
    }

    /* Section 通用规范 */
    section {
      padding: 70px 0;
    }

    .section-head {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px auto;
    }

    .section-badge {
      display: inline-block;
      padding: 4px 14px;
      font-size: 0.8rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: 0.05em;
      border-radius: 20px;
      margin-bottom: 12px;
      background: rgba(79, 70, 229, 0.1);
      color: var(--primary);
      border: 1px solid rgba(79, 70, 229, 0.2);
    }

    .section-badge.badge-orange {
      background: rgba(255, 87, 34, 0.1);
      color: var(--secondary);
      border-color: rgba(255, 87, 34, 0.2);
    }

    .section-badge.badge-cyan {
      background: rgba(6, 182, 212, 0.1);
      color: #0891b2;
      border-color: rgba(6, 182, 212, 0.2);
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 900;
      color: var(--dark-text);
      margin-bottom: 14px;
      line-height: 1.25;
    }

    .section-desc {
      font-size: 1.05rem;
      color: var(--muted-text);
      line-height: 1.7;
    }

    /* 首屏 Hero (无图片) */
    .hero-section {
      padding: 80px 0 60px 0;
      position: relative;
      background: linear-gradient(180deg, rgba(255,255,255,0.8) 0%, rgba(248,250,252,0.6) 100%);
      border-bottom: 1px solid var(--card-border);
    }

    .hero-content {
      text-align: center;
      max-width: 960px;
      margin: 0 auto;
    }

    .hero-pill {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: #ffffff;
      padding: 6px 16px;
      border-radius: 50px;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 700;
      font-size: 0.88rem;
      margin-bottom: 24px;
      box-shadow: 0 4px 14px rgba(79, 70, 229, 0.12);
    }

    .hero-title {
      font-size: 3rem;
      font-weight: 900;
      line-height: 1.2;
      margin-bottom: 20px;
      color: var(--dark-text);
    }

    .hero-title .highlight-gradient {
      background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-lead {
      font-size: 1.2rem;
      color: var(--muted-text);
      margin-bottom: 36px;
      line-height: 1.8;
      max-width: 820px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-buttons {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 16px;
      margin-bottom: 50px;
    }

    .btn-main-brand {
      background: linear-gradient(135deg, var(--secondary) 0%, #e64a19 100%);
      color: #ffffff !important;
      font-size: 1.12rem;
      font-weight: 800;
      padding: 15px 36px;
      border-radius: 12px;
      box-shadow: 0 10px 25px rgba(255, 87, 34, 0.35);
      border: 2px solid #ffffff;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .btn-main-brand:hover {
      transform: translateY(-3px) scale(1.02);
      box-shadow: 0 14px 30px rgba(255, 87, 34, 0.45);
    }

    .btn-main-outline {
      background: #ffffff;
      color: var(--primary) !important;
      font-size: 1.05rem;
      font-weight: 700;
      padding: 14px 28px;
      border-radius: 12px;
      border: 2px solid var(--primary);
      transition: all 0.2s ease;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .btn-main-outline:hover {
      background: rgba(79, 70, 229, 0.05);
      transform: translateY(-2px);
    }

    /* 纯 CSS 科技数据卡片 */
    .hero-stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
      margin-top: 20px;
    }

    .stat-card {
      background: #ffffff;
      padding: 22px 18px;
      border-radius: 16px;
      border: 2px solid var(--card-border);
      text-align: center;
      box-shadow: 0 6px 16px rgba(15, 23, 42, 0.04);
      transition: transform 0.2s, border-color 0.2s;
    }

    .stat-card:hover {
      transform: translateY(-4px);
      border-color: var(--primary);
    }

    .stat-number {
      font-size: 2rem;
      font-weight: 900;
      color: var(--primary);
      margin-bottom: 4px;
      display: block;
    }

    .stat-number.accent {
      color: var(--secondary);
    }

    .stat-label {
      font-size: 0.88rem;
      color: var(--muted-text);
      font-weight: 600;
    }

    /* 基础卡片栅格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }

    .card-box {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 18px;
      padding: 28px;
      box-shadow: 0 4px 18px rgba(15, 23, 42, 0.03);
      transition: all 0.25s ease;
      display: flex;
      flex-direction: column;
    }

    .card-box:hover {
      border-color: var(--primary);
      transform: translateY(-4px);
      box-shadow: 0 12px 28px rgba(79, 70, 229, 0.1);
    }

    .card-tag {
      align-self: flex-start;
      background: rgba(79, 70, 229, 0.1);
      color: var(--primary);
      font-size: 0.78rem;
      font-weight: 800;
      padding: 3px 10px;
      border-radius: 6px;
      margin-bottom: 14px;
    }

    .card-title {
      font-size: 1.25rem;
      font-weight: 800;
      color: var(--dark-text);
      margin-bottom: 10px;
    }

    .card-desc {
      font-size: 0.94rem;
      color: var(--muted-text);
      line-height: 1.65;
      margin-bottom: 16px;
      flex-grow: 1;
    }

    .card-footer-info {
      font-size: 0.85rem;
      font-weight: 700;
      color: var(--secondary);
      border-top: 1px dashed var(--card-border);
      padding-top: 12px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    /* 多模型生态徽章云 */
    .model-badge-wrapper {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      justify-content: center;
      margin-top: 24px;
    }

    .model-chip {
      background: #ffffff;
      border: 1.5px solid #cbd5e1;
      padding: 8px 16px;
      border-radius: 30px;
      font-size: 0.88rem;
      font-weight: 700;
      color: var(--dark-text);
      box-shadow: 0 2px 6px rgba(0,0,0,0.03);
      transition: all 0.2s;
    }

    .model-chip:hover {
      border-color: var(--primary);
      background: var(--primary);
      color: #ffffff;
      transform: translateY(-2px);
    }

    /* 对比评测表格 */
    .comparison-table-wrap {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 20px;
      overflow-x: auto;
      box-shadow: 0 10px 30px rgba(15, 23, 42, 0.05);
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 680px;
    }

    .compare-table th,
    .compare-table td {
      padding: 18px 24px;
      border-bottom: 1px solid var(--card-border);
    }

    .compare-table th {
      background: #f1f5f9;
      font-size: 1rem;
      font-weight: 800;
      color: var(--dark-text);
    }

    .compare-table tr:last-child td {
      border-bottom: none;
    }

    .compare-table .highlight-col {
      background: rgba(79, 70, 229, 0.04);
      font-weight: 700;
      color: var(--primary);
    }

    .score-badge-card {
      background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
      color: #ffffff;
      border-radius: 18px;
      padding: 30px;
      text-align: center;
      margin-bottom: 24px;
    }

    .score-rating {
      font-size: 3.5rem;
      font-weight: 900;
      line-height: 1;
      margin: 10px 0;
    }

    /* 流程步骤 */
    .process-timeline {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .process-card {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 16px;
      padding: 24px;
      position: relative;
    }

    .process-num {
      width: 42px;
      height: 42px;
      border-radius: 12px;
      background: var(--secondary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.2rem;
      font-weight: 900;
      margin-bottom: 16px;
    }

    /* 案例展示带图容器 */
    .media-card {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 18px;
      overflow: hidden;
      box-shadow: 0 4px 18px rgba(15, 23, 42, 0.03);
    }

    .media-container {
      width: 100%;
      background: #e2e8f0;
      overflow: hidden;
    }

    .media-container img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      transition: transform 0.3s ease;
    }

    .media-card:hover img {
      transform: scale(1.03);
    }

    .media-body {
      padding: 24px;
    }

    /* 评论卡片 */
    .review-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .review-card {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 18px;
      padding: 24px;
      box-shadow: 0 4px 16px rgba(15, 23, 42, 0.03);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-text {
      font-size: 0.94rem;
      color: var(--muted-text);
      line-height: 1.7;
      margin-bottom: 18px;
    }

    .reviewer-meta {
      display: flex;
      align-items: center;
      gap: 12px;
      border-top: 1px solid #f1f5f9;
      padding-top: 14px;
    }

    .reviewer-avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.1rem;
    }

    .reviewer-name {
      font-weight: 800;
      font-size: 0.95rem;
      color: var(--dark-text);
    }

    .reviewer-role {
      font-size: 0.8rem;
      color: var(--light-text);
    }

    /* FAQ 折叠面板 */
    .faq-wrapper {
      max-width: 880px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .faq-item {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 14px;
      overflow: hidden;
      transition: border-color 0.2s;
    }

    .faq-item.active {
      border-color: var(--primary);
    }

    .faq-question {
      padding: 20px 24px;
      font-weight: 800;
      font-size: 1.05rem;
      color: var(--dark-text);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
    }

    .faq-question::after {
      content: "+";
      font-size: 1.4rem;
      font-weight: 700;
      color: var(--primary);
      transition: transform 0.2s;
    }

    .faq-item.active .faq-question::after {
      content: "-";
    }

    .faq-answer {
      display: none;
      padding: 0 24px 20px 24px;
      font-size: 0.95rem;
      color: var(--muted-text);
      line-height: 1.7;
      border-top: 1px dashed #f1f5f9;
      padding-top: 14px;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    /* 表单区域 */
    .form-wrapper-box {
      background: #ffffff;
      border: 2px solid var(--card-border);
      border-radius: 20px;
      padding: 40px;
      box-shadow: 0 8px 24px rgba(15, 23, 42, 0.04);
    }

    .form-grid-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }

    .form-group-full {
      grid-column: span 2;
    }

    .form-control {
      width: 100%;
      padding: 13px 16px;
      border: 2px solid var(--card-border);
      border-radius: 10px;
      font-size: 0.95rem;
      outline: none;
      background: #fafafa;
      color: var(--dark-text);
      transition: border-color 0.2s;
    }

    .form-control:focus {
      border-color: var(--primary);
      background: #ffffff;
    }

    .btn-submit {
      background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
      color: #ffffff;
      font-size: 1.05rem;
      font-weight: 800;
      padding: 15px;
      border: none;
      border-radius: 10px;
      cursor: pointer;
      width: 100%;
      transition: opacity 0.2s, transform 0.2s;
    }

    .btn-submit:hover {
      opacity: 0.95;
      transform: translateY(-2px);
    }

    /* 行业资讯文章列表 */
    .article-link-list {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 20px;
    }

    .article-chip-link {
      background: #ffffff;
      border: 1px solid var(--card-border);
      padding: 8px 16px;
      border-radius: 8px;
      font-size: 0.88rem;
      color: var(--muted-text);
      font-weight: 600;
      transition: all 0.2s;
    }

    .article-chip-link:hover {
      border-color: var(--primary);
      color: var(--primary);
    }

    /* 悬浮客服 */
    .floating-contact-panel {
      position: fixed;
      right: 20px;
      bottom: 40px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .floating-btn {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.2rem;
      box-shadow: 0 4px 16px rgba(0,0,0,0.15);
      cursor: pointer;
      border: 2px solid #ffffff;
      transition: transform 0.2s, background 0.2s;
    }

    .floating-btn:hover {
      transform: scale(1.1);
      background: var(--secondary);
    }

    /* 页脚 */
    footer.site-footer {
      background: #0f172a;
      color: #cbd5e1;
      padding: 60px 0 24px 0;
      border-top: 4px solid var(--primary);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 36px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 1.1rem;
      font-weight: 800;
      margin-bottom: 18px;
      border-left: 3px solid var(--secondary);
      padding-left: 10px;
    }

    .footer-col p {
      font-size: 0.9rem;
      line-height: 1.8;
      color: #94a3b8;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .footer-links a {
      color: #94a3b8;
      font-size: 0.9rem;
      transition: color 0.2s;
    }

    .footer-links a:hover {
      color: #ffffff;
    }

    .footer-qr-box {
      background: #1e293b;
      padding: 12px;
      border-radius: 12px;
      display: inline-block;
      text-align: center;
    }

    .footer-qr-box img {
      width: 110px;
      height: 110px;
      display: block;
      border-radius: 6px;
    }

    .footer-friendly-links {
      border-top: 1px solid #1e293b;
      padding: 20px 0;
      font-size: 0.85rem;
      color: #64748b;
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
    }

    .footer-friendly-links a {
      color: #94a3b8;
      text-decoration: underline;
    }

    .footer-bottom {
      border-top: 1px solid #1e293b;
      padding-top: 20px;
      text-align: center;
      font-size: 0.85rem;
      color: #64748b;
    }

    /* 响应式调整 */
    @media (max-width: 992px) {
      .hero-title { font-size: 2.2rem; }
      .hero-stats-grid { grid-template-columns: repeat(2, 1fr); }
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .process-timeline { grid-template-columns: repeat(2, 1fr); }
      .review-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.1);
        border-bottom: 2px solid var(--primary);
      }
      .nav-links.active { display: flex; }
      .mobile-menu-toggle { display: block; }
      .hero-title { font-size: 1.8rem; }
      .grid-3, .grid-2, .grid-4, .review-grid, .process-timeline, .form-grid-layout, .footer-grid {
        grid-template-columns: 1fr;
      }
      .form-group-full { grid-column: span 1; }
      .form-wrapper-box { padding: 20px; }
      .floating-contact-panel { right: 12px; bottom: 20px; }
    }